This article was first written in June 2004 for the BeezNest technical
website (http://glasnost.beeznest.org/articles/134).
PostgreSQL Autodoc is a powerful and useful tool to document a PostgreSQL  database. It is written in Perl  and generates several outputs.
Using it is as simple as launching it with the name of the DB, and user  and password to connect to it. See 
postgresql_autodoc --help for  help.
The 
Dia output is not really useful or practical, because all the tables will get  on the same place of the Dia document (ie they will all be on top of each  other).
The Dot output is a text output meant to be processed by 
GraphViz (or a compatible program such as 
Springgraph) to generate graph from it.
It seemed particularly difficult to get a printed version, so I explain  here how I got it to work for a medium-sized graph on an A3 printer, on  a Debian  system with packages 
graphviz and 
mpage and 
xpp installed.
I used dotty which is a graphical tool to see and edit the .dot  file. To print it, I went into the menu available on right-click and 
print  graph. There, it asks if you want to print on a file (PostScript output)  or on a printer. I chose 
printer. There, it asks which command-line  to use to print. I replaced the call from lpr to xpp,  which is interactive. There, it asks for the size and orientation you want.  Choose whatever best suite your needs (ie the size of your DB schema).  I chose 
11x17 and 
best fit and it launched 
XPP, where I changed page size to 
A3 and  clicked on button 
Print.
And guess what? I have my schema printed as I like!